A company A filed my H1 B transfer and it is approved now.I have never worked for company A. I have another company B willing to file my VISA. I have below questions.

1. Is there any issue if company B files my transfer, though I can not provide the approved petition by compoany A. I can only give the petition of my current company.
2. I have accepted the offer from company A so as to file the transfer. Can they cause any legal trouble if I do not join them.